Planar versus non-planar: The important role of weak C—H⋯O hydrogen bonds in the crystal structure of 5-methyl­salicyl­aldehyde

Acta Crystallographica Section E: Crystallographic Communications

Nä¹  Baisch, U.²  Scicluna, M.C.²  Vella-Zarb, L.²  ther, C.³ 

[1] Anorganische Chemie, Christian-Albrechts-UniversitäDepartment of Chemistry, University of Malta, Msida, MSD 2080, Malta;t zu Kiel, Max-Eyth-Str 2, 24118 Kiel, Germany

关键词: CRYSTAL STRUCTURE;    5-MSA;    ORGANIC;    SALICYLIC ACID;    HYDROGEN BONDS;   

DOI  :  10.1107/S2056989017000238

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

The crystal structure of 5-methyl­salicyl­aldehyde (5-MSA; systematic name 2-hy­droxy-5-methyl­benzaldehyde), C8H8O2, was discovered to be a textbook example of the drastic structural changes caused by just a few weak C—H⋯O inter­actions due to the additional methyl­ation of the aromatic ring compared to salicyl­aldehyde SA. This weak inter­molecular hydrogen bonding is observed between aromatic or methyl carbon donor atoms and hydroxyl or aldehyde acceptor oxygen atoms with d(D⋯A) = 3.4801 (18) and 3.499 (11) Å. The mol­ecule shows a distorted geometry of the aromatic ring with elongated bonds in the vicinity of substituted aldehyde and hydroxyl carbon atoms. The methyl hydrogen atoms are disordered over two sets of sites with occupancies of 0.69 (2) and 0.31 (2).

【 授权许可】

CC BY